1. What is the difference between incidence and prevalence? How are they calculated? - Incidence is the number of new cases of a disease or condition in a population over a period of time, usually expressed as a rate per 1000 or 100,000 people. Prevalence is the proportion of people in a population who have a disease or condition at a given point in time, usually expressed as a percentage. They are calculated as follows: - Incidence rate = (number of new cases in a period / population at risk at the start of the period) x 1000 (or 100,000) - Prevalence = (number of existing cases at a point in time / population at that point in time) x 100 2. What are the advantages and disadvantages of using mortality rates as a measure of disease burden? - Mortality rates are the number of deaths from a disease or condition in a population over a period of time, usually expressed as a rate per 1000 or 100,000 people. Some advantages of using mortality rates are: - They are easy to obtain from vital statistics and death certificates - They reflect the severity and outcome of a disease or condition - They can be used to compare different populations or regions - Some disadvantages of using mortality rates are: - They do not capture the morbidity or quality of life of people living with a disease or condition - They may be affected by factors such as age structure, access to health care, and cause of death classification - They may not reflect the true incidence or prevalence of a disease or condition, especially if it has a low fatality rate or a long latency period